..Thus, the extent of qE measured as either the fractional intensities of the PSII chlorophyll a fluorescence lifetime distributions or steady state intensities was stoichiometrically related to the amount of PsbS protein...

Carotenoid cation formation and the regulation of photosynthetic light harvesting

..These results indicate that energy transfer from chlorophyll molecules to a chlorophyllzeaxanthin heterodimer, which then undergoes charge separation, is the mechanism for excess energy dissipation during feedback deexcitation...

..Furthermore, based on the extent of qE inhibition in the mutants, photochemical and nonphotochemical quenching processes of photosystem II were associated with distinct chlorophyll fluorescence life-time distribution components...

..Both physiological and molecular characterization of the npq5 mutant suggest that most thermal dissipation within LHCII of Chlamydomonas is dependent on the peripherally associated trimeric LHC polypeptides...

..Taken together, these results suggest that the replacement of alpha-tocopherol by beta-tocopherol in a xanthophyll-deficient strain of Chlamydomonas reinhardtii contributes to better survival under conditions of photooxidative stress...

..Neither QTL maps to a gene that had been identified previously in extensive forward genetics screens using induced mutants, suggesting that quantitative genetics can be used to find new genes affecting thermal dissipation...

Lutein can act as a switchable charge transfer quencher in the CP26 light-harvesting complex

..We also show that lutein radical cation formation in CP26 is dependent on binding of zeaxanthin to the L2 domain, implying that zeaxanthin acts as an allosteric effector of charge transfer quenching involving lutein in the L1 domain...

Trophic status of Chlamydomonas reinhardtii influences the impact of iron deficiency on photosynthesis

..The bleaching phenotype of npq1 lor1 was not due to enhanced photodamage to photosystem II but rather to a less localized phenomenon of accumulation of photo-oxidation products in chloroplast membranes...

..A paa1 paa2 double mutant was seedling-lethal, underscoring the importance of copper to photosynthesis. We propose that PAA1 and PAA2 function sequentially in copper transport over the envelope and thylakoid membrane, respectively...